Endocrine Abstracts

All evidence so far indicates a role of different connexins during gonadal development, gamete formation and testicular and ovarian functions. Connexin 43 (Cx43) is one of the predominant gap junction proteins in the testis and ovary. It is well established that gonads development is highly sensitive to hormonal disruption induced by various endocrine active compounds during fetal period. Therefore, it was interesting to study whether communication via gap junctions is altered in gonads of pig fetuses exposed to anti-androgen flutamide prenatally. To perform this project, pregnant sows were injected with flutamide (50 mg/kg body weight, seven times, every day) starting at 83 or 101 day of gestation. On days 90 and 108 the fetuses were excised during a surgical procedure. Fetal gonads were fixed in Bouin’s fixative for immunohistochemistry or frozen in liquid nitrogen for real-time PCR analysis. Immunohistochemistry was performed on tissue sections using a polyclonal rabbit antibody against Cx43 (dilution 1:2000; Sigma–Aldrich) followed by a goat anti-rabbit IgG (dilution 1:300; Vector Lab.) and the standard ABC method. Binding of antibody to the antigen was visualized by diaminobenzidine. To assess Cx43 mRNA expression real-time PCR was performed using the TaqMan Gene Expression Assay (Applied Biosystems).

In the fetal ovaries, Cx43 protein was localized between interstitial cells surrounding egg nests and between granulosa cells of primary follicles. In the fetal testes, Cx43 was detected between Leydig cells. In the fetal gonads Cx43 expression was up-regulated after flutamide treatment.

Detection of changes in Cx43 gene expression in developing porcine fetal gonads after exposure to flutamide may indicate the role of androgens in the regulation of cell-to-cell communication within the testes and ovaries.

Supported by Iuventus Plus grant (IP2011 024571) of the Polish Ministry of Science and Higher Education.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This work was supported, however funding details unavailable.